COMPARISON OF DIFFERENT MICROWAVE-BASED DIGESTION TECHNIQUES IN VIEW OF THEIR APPLICATION TO FAT-RICH FOODS

Three different microwave-based digestion techniques are tested with a view to the determination of heavy metals in the ashing solutions of fat-rich foods of up to 98% fat content. The known dissolution techniques are amended with respect to the fatty matrix. Advantages and disadvantages are compared with the "Tolg" procedure and discussed in consideration of the reproducibility, carbon residue contents, losses of analyte, trace contamination, ashing time and the possibility of automation of the dissolution process. A pressurized dissolution technique in PTFE-lined vessels is shown to be the most promising procedure.